Illegal alien is the old term. I’m sure the OP meant no offense. She actually used undocumented, which now is the preferred term to illegal. So, from everything I’ve heard of late, we should be saying undocumented immigrant. I still think in my head illegal alien, and then fix it before I actually say it write it.
The biggest reason people don’t do it legally is fear of being rejected. America still has quotas, and especially if you are from countries that quickly fill quotas the line to get in can be long. A perfect example is Mexico. Also, take into consideration that immigrants from Mexico have an average education of 8th grade. So, let’s say you have a 5th grade education, barely speak English, you can barely feed your family, and a guy you know knows how to cross the border and get you work. Are you likely to apply for paperwork?
Many do enter legally on tourist visas and school visas and overstay, or work when they are not allowed. The ones who overstay are here illegally, so their afraid to alert the government they are here. If they are here legally on tourist visas, you can’t just easily turn it into a permanent resident visa. Lots of those people get married (pay someone to marry them sometimes) or there have been times we have had lotteries or different ways to put your name in to get proper paperwork.
People with specific skills can get sponsored by their employer. Parents can be brought her by adult children who are citizens, but you sign that you are responsible for them. Basically, you are sponsoring them. You cannot do this for siblings or adult children.
My girlfriends sister was rejected. She applied for entry under a student visa. She was already accepted at University of Mississippi. All of her siblings live in America. The US rejected her application citing they didn’t believe she would return home. She is from Venezuela.
For people like my husband he had to do it legally, because one, it’s simply his personality, he would never be comfortable doing it under the table. Two, he was a corporate guy, and corporations don’t hire undocumented managers. Unless, that manager is using a false SS# and has gone to the extent to have all the false documents he needs to trick employers. If you’re a busboy, a farm hand, maid, etc, those industries are used to being paid under the table.
It’s much easier to get papers if you’re Italian than if your from Mexico.